U.S. Pat. No. 4,104,019 discloses apparatus and method for fixation of dyes and other chemicals in textile fibers, however formed or combined, wherein the textile fibrous materials are wetted with dye or other chemicals and are continuously mechanically conveyed through a closely confined tube located between electrodes which create a radio frequency (RF) energy field in the tube. The fibrous material is packed within the tube during its passage therethrough so as to provide a partially self-sealing pressure chamber therein due to generation of steam whereby the rate of reaction of the dye or chemical on the fibers is accelerated.
As shown in FIG. 3 of the patent, loose fibrous materials are continuously conveyed by suitable conveyors to a liquid dye or chemical padding unit. The fibers are gravitationally delivered by a conveyor chute into the padding unit which contains a moving belt having an amount, or level, of liquid dye or chemical thereon. The dye or chemical transfers into the fibrous material as it is fed to the nip of a double roller mangle comprising an upper drum and a lower drum over which the belt passes. The pressure of the roller mangle expresses the dye or chemical from the wetted fibers to obtain a desired wet pick-up, after which the fibers are continuously directed into an elongate RF energy heating tube where they are compacted during heat fixation.
It is also known in such equipment as described in U.S. Pat. No. 4,104,019 to utilize a fiber-receiving hopper for receiving the wetted fibrous material from the padding unit and delivering the same under compression into the RF heating tube. The hopper has an open top for gravitationally receiving the wetted fibrous material in a continous stream, or flow, into a lower fiber compression chamber which communicates with the RF energy heating tube. A fluid-actuated ram cycles through the hopper compression chamber to compress and pack the fibrous material into and push it through the heating tube. The compressed fibrous material moving through the tube is heated by RF energy to react or fix the dye or chemical on the fibers, and the material leaves the heating tube against the action of a reduced back pressure piston, after which it is washed, dried and collected in suitable manner.
The apparatus and process above described provides the advantages of a continuous dyeing operation utilizing less energy consumption that the conventional discontinous batch dyeing operations heretofore employed in the prior art. Such apparatus and process also permits effective uniform dyeing of loose fibrous materials with lesser amounts of dye liquid than the prior art batch dyeing operations. Typically, fibrous materials in loose form can be uniformly and effectively dyed utilizing a wet pick-up of dye composition of as low as 100% on the textile fibers.
In the use of the above-described apparatus, the compressed fibrous materials exiting the heating tube against the action of the reduced back pressure piston are discharged intermittently in highly compressed fiber mass sections, or "cakes", and these sections are deposited onto a moving conveyor for subsequent washing, drying, and collection. It is desirable that the loose fibers be thoroughly washed with a suitable washing liquid after heating to ensure that excess chemical or dyes be removed from the fibers before drying and collection. Because of the highly compacted condition of the compressed fiber cakes leaving the confined heating tube, it has been difficult to satisfactorily open the fiber cakes for uniformly washing the individual loose fibers during the continuous treating operation.
It is therefore an object of the present invention to provide improved chemical or dye treating apparatus of the type described wherein means are provided for effectively breaking apart and opening dyed or chemically treated compressed fiber mass sections, or cakes, to uniformly wash the fibers before collection.
It is another object of the invention to provide for the more uniform chemical or dye treatment of textile fibers in a continuous treating operation wherein compressed fibrous mass sections, or cakes, are effectively uniformly broken apart and spread for uniform washing of the fibers during their continuous movement through the apparatus.